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An approach for automatic sleep stage scoring and apnea-hypopnea detection

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Frontiers of Computer Science 2012年第2期6卷 230-241页

作者： TimSCHLǔter StefanCONRAD InstituteofComputerScience HeinrichHeineUniversity40225DtisseldorfGermany

In this article we present an application of data mining to the medical domain sleep research, an approach for automatic sleep stage scoring and apnea-hypopnea detec- tion. By several combined techniques （Fourier and wavelet transform, derivative dynamic time warping, and waveform recognition）, our approach extracts meaningful features （fre- quencies and special patterns like k-complexes and sleep spindles） from physiological recordings containing EEG, ECG, EOG and EMG data. Based on these pieces of in- formation, an ensemble of decision trees is constructed us- ing the principle of bagging, which classifies sleep epochs in their sleep stages according to the rules by Rechtschaf- fen and Kales and annotates occurrences of apnea-hypopnea （total or partial cessation of respiration）. After that, case- based reasoning is applied in order to improve quality. We tested and evaluated our approach on several large public databases from PhysioBank, which showed an overall accu- racy of 95.2% for sleep stage scoring and 94.5% for classify- ing minutes as apneic or non-apneic.

关键词： time series data processing signal processing,feature extraction pattern classification biomedical signalprocessing sleep

An L-band emitter with quantum memory in silicon

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npj Computational Materials 2022年第1期8卷 2498-2503页

作者： Péter Udvarhelyi Anton Pershin Péter Deák Adam Gali Wigner Research Centre for Physics P.O.Box 49H-1525BudapestHungary Budapest University of Technology and Economics Institute of PhysicsDepartment of Atomic PhysicsMűegyetem rakpart 3.1111BudapestHungary

Fluorescent centres in silicon have recently attracted great interest,owing to their remarkable properties for quantum ***,we demonstrate that the C-centre in silicon can realise an optically readable quantum register in the L-band wavelength region where the transmission losses in commercial optical fibres are *** in-depth theoretical characterisation confirms the assignment of the C-centre to the carbon-oxygen interstitial pair *** further explore its magneto-optical properties,such as hyperfine and spin-orbit coupling constants from first principles calculations,which are crucial for tight control of the quantum states of the triplet electron *** on this data,we set up quantum optics protocols to initialise and read out the quantum states of the electron spin,and realise a quantum memory by transferring quantum information from the electron spin to proximate ^(29)Si nuclear *** findings establish an optically readable long-living quantum memory in silicon where the scalability of qubits may be achieved by CMOS-compatible technology.

关键词： quantum centre optics

Occult hepatitis B virus infection:A complex entity with relevant clinical implications

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World Journal of Gastroenterology 2011年第12期17卷 1529-1530页

作者： Juan-ramon Larrubia Translational Hepatology Unit Guadalajara University Hospital University of Alcalá

Occult hepatitis B virus(HBV) infection is a world-wide entity,following the geographical distribution of detectable hepatitis *** entity is defined as the persistence of viral genomes in the liver tissue and in some instances also in the serum,associated to negative HBV surface antigen *** molecular basis of the occult infection is related to the life cycle of HBV,which produces a covalently closed circular DNA that persists in the cell nuclei as an episome,and serves as a template for gene *** mechanism responsible for the HBsAg negative status in occult HBV carriers is a strong suppression of viral replication,probably due to the host’s immune response,co-infection with other infectious agents and epigenetic *** is emerging evidence of the potential clinical relevance of occult HBV infection,since this could be involved in occult HBV transmission through orthotopic liver transplant and blood transfusion,reactivation of HBV infection during immunosuppression,impairing chronic liver disease outcome and acting as a risk factor for hepatocellular *** it is important to bear in mind this entity in cryptogenetic liver diseases,hepatitis C virus/ HIV infected patients and immunosupressed *** is also necessary to increase our knowledge in this fascinating field to define better strategies to diagnose and treat this infection.

关键词： Hepatitis B virus Occult infection Persistent infection

Anatomical basis for pancreas transplantation via isolated splenic artery perfusion:A literature review

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World Journal of Clinical Cases 2022年第35期10卷 12844-12853页

作者： Ilya Dmitriev Marine oganesyan Antonina Popova Egor Orlov Mikhail Sinelnikov Yury Zharikov Department of Pancreas and Kidney Transplantation N.V.Sklifosovsky Research Institute for Emergency CareMoscow 107045Russia Department of Human Anatomy Sechenov First Moscow State Medical University(Sechenov University)Moscow 125009Russia Department of Oncology Radiotherapy and Reconstructive SurgerySechenov First Moscow State Medical University(Sechenov University)Moscow 119048Russia Laboratory of clinical morphology Research Institute of Human MorphologyMoscow 117418Russia

The variability of vascular anatomy of the pancreas underlines the difficulty of its *** regarding the consistency of anatomical variations shows splenic arterial dominance in most *** can significantly improve transplantation success.A systematic literature review was performed according to the quality standards described in the AMSTAR measurement tool and the PRISMA *** valuated existing literature regarding the vascularization and blood perfusion patterns of the pancreas in terms of dominance and *** collected data was independently analyzed by two *** of vascular anatomy was seen to be underreported in literature,though significant findings have been included and discussed in this study,providing valuable insight into the dynamics of pancreatic perfusion and feasibility of transplantation on several different supplying *** splenic artery(SA)has a high percentage of consistency in all found studies(over 90%).High frequency of anastomoses between arterial pools supplying the pancreas can mediate sufficient blood supply through a dominant vessel,such as the SA,which is present in most *** transplantation with isolated SA blood supply can provide sufficient arterial perfusion of the pancreas for stable transplant viability due to high anatomical consistency of the SA and vast communications with other arterial systems.

关键词： Pancreas transplantation Isolated splenic artery supply Pancreas anatomy pancreatic perfusion Minireview

Large eddy simulations of a turbulent mixing layer periodically excited with fundamental and third harmonic frequency

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Chinese Journal of Aeronautics 2023年第5期36卷 33-40页

作者： Jörg SCHLÜter Dan ZHAO Abhishek SARKAR School of Engineering Deakin UniversityWaurn Ponds 3216Australia College of Engineering University of CanterburyChristchurch 8041New Zealand School of Mechanical and Aerospace Engineering Nanyang Technological UniversitySingapore

A better understanding of the mixing behavior of excited turbulent mixing layers is critical to a number of aerospace *** studies of excited turbulent mixing layers focused on single frequency excitation or the excitation with fundamental and its second harmonic *** is a lack of detailed studies on applying low and higher frequency *** this study,we have performed large-eddy simulations of periodically excited turbulent mixing *** excitation consists of a fundamental frequency and its third *** have used phase-averaging to identify the vortex structure and strength in the mixing layer,and we have studied the vortex *** different vortex paring mechanisms are observed depending on the phase shift between the two excitation *** influence of these two mechanisms on the mixing of a passive scalar is also *** is found that exciting the mixing layer with these low and high frequencies has initially an adverse influence on the mixing process;however,it improves the mixing further downstream of the splitter plate with the excitation using a phase shift ofΔφ=πshowing the best mixing *** present works shed lights on the fundamental vortex dynamics,and has great potential for aeronautical,automotive and combustion engineering applications.

关键词： Flow control Flow excitation Large eddy simulations Turbulent mixing layer Vortex dynamics

Crystallographically Selective Nanopatterning of Graphene on SiO_(2)

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Nano Research 2010年第2期3卷 110-116页

作者： Péter Nemes-Incze Gábor Magda Katalin Kamarás LászlóPéter Biró Research Institute for Technical Physics and Materials Science PO Box 49H-1525 BudapestHungary Budapest University of Technology and Economics(BME) PO Box 91H-1521 BudapestHungary Research Institute for Solid State Physics and Optics Hungarian Academy of SciencesPO Box 49H-1525 BudapestHungary

Graphene has many advantageous properties,but its lack of an electronic band gap makes this two-dimensional material impractical for many nanoelectronic applications,for example,field-effect *** problem can be circumvented by opening up a confinement-induced gap,through the patterning of graphene into ribbons having widths of a few *** electronic properties of such ribbons depend on both their size and the crystallographic orientation of the ribbon ***,etching processes that are able to differentiate between the zigzag and armchair type edge terminations of graphene are highly sought *** this contribution we show that such an anisotropic,dry etching reaction is possible and we use it to obtain graphene ribbons with zigzag *** demonstrate that the starting positions for the carbon removal reaction can be tailored at will with precision.

关键词： Graphene atomic force microscopy(AFM) etching nanoribbon zigzag

Smooth free-cycle dynamic soaring in unspecified shear wind via quadratic programming

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Chinese Journal of Aeronautics 2022年第7期35卷 19-29页

作者： Haichao HONG Benedikt GRüter Patrick PIPREK Florian HOLZAPFEL Institute of Flight System Dynamics Technical University of MunichGarching D-85748Germany

Harvesting wind energy is promising for extending long-endurance flights,which can be greatly facilitated by a flight technique called dynamic *** presented study is concerned with generating model-based trajectories with smooth control histories for dynamic soaring maneuvers exploiting wind *** desired smoothness is achieved by introducing a trigonometric series parameterization for the controls,which are formulated with respect to the normalized ***,the periodicity of the trigonometric functions is leveraged to facilitate the connection of cycles and streamline the problem *** relying on a specified wind profile,a freefinal-time quadratic programming-based control strategy is developed for the online correction of the flight trajectory,which requires only the instant wind *** and online numerical studies show the trade-off to achieve the smoothness and demonstrate the effectiveness of the proposed method in a varying wind field.

关键词： Dynamic soaring Optimal control Quadratic programming Trajectory generation Trigonometric series

Bioelectrochemistry for flexible control of biological processes

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Environmental Science and Ecotechnology 2020年第1期1卷 83-84页

作者： Annemiek ter Heijne Environmental Technology Wageningen University&ResearchBornse Weilanden 96708 WGWageningenthe Netherlands

Societal awareness and worries about the future of the earth are rapidly *** does not want to contribute to a sustainable future,in which the earth’s resources will still be available for future generations?In my view,a sustainable world is a world in which we live in close collaboration with *** nature,microorganisms are a key player in the global carbon,nitrogen and phosphorous cycle.

关键词： earth sustainable collaboration

Rifaximin,but not growth factor 1,reduces brain edema in cirrhotic rats

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World Journal of Gastroenterology 2012年第17期18卷 2084-2091页

作者： Gemmaòdena Mireia Miquel Anna Serafín Amparo Galan Rosa Morillas ramon Planas ramon Bartolí Hepatology Unit Department of GastroenterologyGermans Trias i Pujol Health Science Research Institute08916 BadalonaSpain Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas(CIBERehd) 08036 BarcelonaSpain Department of Gastroenterology CorporacióSanitària Parc Taulí08208 SabadellSpain Platform of Laboratory Animal Applied Research Parc Científic de Barcelona08028 BarcelonaSpain Department of Biochemistry Hospital Universitari Germans Trias i Pujol08916 BadalonaSpain Liver Unit Department of GastroenterologyHospital Universitari Germans Trias i Pujol08916 BadalonaSpain

AIM:To compare rifaximin and insulin-like growth factor(IGF)-1 treatment of hyperammonemia and brain edema in cirrhotic rats with portal ***:Rats with CCl4-induced cirrhosis with ascites plus portal vein occlusion and controls were randomized into six groups:Cirrhosis;Cirrhosis + IGF-1;Cirrhosis + rifaximin;Controls;Controls + IGF-1;and Controls + *** oral glutamine-challenge test was performed,and plasma and cerebral ammonia,glucose,bilirubin,transaminases,endotoxemia,brain water content and ileocecal cultures were measured and liver histology was ***:Rifaximin treatment significantly reduced bacterial overgrowth and endotoxemia compared with cirrhosis groups,and improved some liver function parameters(bilirubin,alanine aminotransferase and aspartate aminotransferase).These effects were associated with a significant reduction in cerebral water *** and cerebral ammonia levels,and area-underthe-curve values for oral glutamine-challenge tests were similar in rifaximin-treated cirrhotic rats and control group *** contrast,IGF-1 administration failed to improve most alterations observed in ***:By reducing gut bacterial overgrowth,only rifaximin was capable of normalizing plasma and brain ammonia and thereby abolishing low-grade brain edema,alterations associated with hepatic encephalopathy.

关键词： Hyperammonemia Low-grade brain edema Hepatic encephalopathy Rifaximin Insulin-like growth factor 1 Cirrhosis